JPH1182093A - Power generation control system of electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a generator and an engine for driving the generator to their operating points that hold generated energy higher and satisfy the temperature conditions of their parts. SOLUTION: If there is a request for power generation, requested generated energy P0 is obtained at first and basic operating points (NO, TO), are set for the best fuel consumption (S101-S105). If the catalyst temperature is lower than a set point, the basic operating points are changed to operating points (Ncold, Tcold) that hold the generated energy P0 and elevate the exhaust temperature (S106-S108). If the temperature of each part is higher than a set point, it is changed to the operating points (Nheat, Theat) that hold the generated energy P0 and lower exhaust temperature (S109-S111). If the temperature of each part is nevertheless higher than the set point, it is changed to operating points (N1heat, T1heat) that lower the exhaust temperature effectively (S112-S113). This routine thus satisfies the temperature conditions of the engine and generator parts while maintaining required generated energy to thereby suppress a deterioration in fuel economy, exhaust performance and parts quality while maintaining sufficient power performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generation control device for an electric vehicle, and more particularly to an engine for driving a generator, a generator driven by a mechanical output of the engine, an electric motor for driving a vehicle, and an electric motor for driving. The present invention relates to a power generation control device for a so-called hybrid electric vehicle including a battery for supplying energy to a motor and charging energy of a generator, and a control device for controlling the battery.

[0002]

2. Description of the Related Art An electric vehicle equipped with a generator and an engine for driving the generator is a series hybrid vehicle (SHEV).
Called. This is intended to increase the cruising distance of an electric vehicle (EV) and to improve the fuel efficiency and exhaust performance of a gasoline engine vehicle by mounting a generator. For example, the battery is charged, that is, the battery is charged. When the state of charge (SOC) is equal to or higher than the set value, the vehicle runs only on the energy of the battery. When the state of charge of the battery decreases, that is, when the SOC decreases below a certain set value, the engine-driven generator is driven. There is known a system or the like that uses this energy to charge the energy of the drive motor or the battery and stops the engine drive generator when the charged amount reaches a predetermined value.

[0003] Incidentally, a series hybrid electric vehicle (SHEV) is expected to further reduce the emission of harmful components. For example, as a control method of a generator and a generator driving engine, for example, an exhaust gas is used. Considering that the catalytic converter attached downstream of the engine exhaust pipe as a purification device has poor exhaust purification performance when the temperature is low (inactive), the engine is operated for idling for a predetermined time after starting the engine, and then the output is increased to about twice the predetermined value. There has been proposed a method of increasing the exhaust gas flow rate and thereby warming up (activating) the catalytic converter early after starting to enhance the exhaust gas purification performance (Japanese Patent Laid-Open No. 5-328).
No. 528, etc.).

[0004]

However, in the conventional control in which the engine output (in other words, the generator load) is increased to about twice the predetermined value for the early activation of the catalytic converter, the required power generation amount is not increased. Since the amount of power generation becomes larger, the battery may be deteriorated.

[0005] In addition, since the engine speed (engine speed) is increased, the engine noise becomes noticeable when the vehicle is stopped or when the vehicle speed is low. There is also. Furthermore, the emission amount of harmful components of exhaust gas (emission amount of HC, CO, NOx, etc .:
/ Min) is the exhaust gas flow rate (for example, 1 / min) × the exhaust harmful component concentration ｛the concentration of HC, CO, NOx, etc. (pp
m) Since｝, increasing the exhaust gas flow rate means
Includes the problem of increasing the risk of increasing emissions of exhaust harmful components.

The present invention has been made in view of such a conventional situation, and among the factors for controlling the power generation amount of the generator,
Electric power generation of an electric vehicle in which the rotation speed is controlled by a generator driving engine and the generator controls the amount of power generation (and thus the engine output) by controlling factors such as torque or output and output current value on the generator side. The control device can maintain the required power generation as much as possible to ensure power performance, noise / vibration performance, suppress battery deterioration, etc., and improve exhaust performance by, for example, early activation of the catalyst. An object of the present invention is to be able to suppress protection, deterioration, and the like.

[0007]

According to the first aspect of the present invention, there is provided an electric motor for driving a vehicle, a chargeable / dischargeable storage battery for supplying power to the electric motor for driving the vehicle,
A generator for generating electric power for supplying electric power to the vehicle driving electric motor or the storage battery; and a generator driving engine for driving the generator, and controlling a power generation amount of the generator. Of the factors to be controlled, the rotation speed is controlled by the generator driving engine, and the other factors are controlled by the generator. The rotation speed of the engine for driving the machine and the control value of the factor controlled on the generator side are changed.

According to the second aspect of the present invention, as shown in FIG. 1, an electric motor for driving a vehicle, a chargeable / dischargeable storage battery for supplying power to the electric motor for driving the vehicle, and an electric motor for driving the vehicle are provided. A generator that generates power for supplying power to the motor or the storage battery, and a generator driving engine that drives the generator, among the factors that control the power generation amount of the generator, In a power generation control device for an electric vehicle in which the rotation speed is controlled by the generator driving engine and other factors are controlled by the generator side, in accordance with the temperature condition of each part, the generator driving engine The apparatus includes a change control means for changing a control value of a rotation speed and a factor controlled on the generator side.

According to the first and second aspects of the present invention, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine) are determined. , For example, can basically achieve the required power generation,
In addition, while power generation (operation) is performed as an efficient operating point, for example, depending on temperature conditions of each part such as a low catalyst temperature (not in an active state) or a high component temperature in an engine room, The operating point is maintained while maintaining the required power generation (required output) as much as possible.
Since it is possible to perform control to change the operating point to a more appropriate operating point according to the temperature condition of each unit, it is possible to satisfy the temperature condition of each unit as much as possible while maintaining the required power generation amount as much as possible. Therefore, it is possible to improve the exhaust performance by, for example, early activation of the catalyst while maintaining the required power generation amount as much as possible and securing the power performance, noise / vibration performance, and suppressing the deterioration of the battery. Deterioration and the like can be suppressed.

According to the third aspect of the present invention, when the temperature condition of each section satisfies a predetermined condition, the control value of the rotation speed of the engine for driving the generator and a factor controlled on the generator side. Can achieve the required power generation, and
It is set so that the efficiency of the generator driving engine can be increased. With this configuration, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine)
As long as the temperature condition of each section satisfies the predetermined condition, the required power generation amount can be achieved, and power generation (operation) can be performed as an efficient operating point. It is possible to minimize the fuel consumption of the generator driving engine while maintaining the amount and ensuring the power performance and the like and suppressing the deterioration of the battery.

According to a fourth aspect of the present invention, when the temperature of the exhaust purification catalyst interposed in the exhaust passage of the generator driving engine is equal to or lower than a set temperature, the rotation speed of the generator driving engine and the rotation speed of the generator driving engine are controlled. The control value of the factor controlled on the generator side is changed so that the required power generation amount can be achieved and the exhaust temperature of the generator driving engine can be increased.

With this configuration, for example, when the catalyst temperature is low (the catalyst is not active), the operating points of the generator and the generator driving engine (the control values of the control factors on the generator side and the generator (The rotational speed of the driving engine) can be set as an operating point at which the required power generation can be achieved and the exhaust gas temperature can be increased, so that power generation (operation) can be performed. The catalyst can be activated as early as possible at the maximum while ensuring the performance and suppressing the deterioration of the battery, and the exhaust performance can be improved.

According to the present invention, the larger the deviation between the temperature of the exhaust gas purification catalyst interposed in the exhaust passage of the engine for driving the generator and the set temperature, the larger the engine for driving the generator. And the control values of the factors controlled on the generator side are changed so that the exhaust temperature of the generator driving engine can be further increased.

With this configuration, the temperature of the exhaust purification catalyst interposed in the exhaust passage of the engine for driving the generator,
When the deviation from the set temperature is large, the exhaust gas temperature can be raised as much as possible to achieve early activation, and when the deviation becomes small, the exhaust gas temperature is decreased accordingly and the operating point is changed to an efficient operating point. Therefore, it is possible to achieve both early activation of the catalyst and reduction of fuel efficiency.

In the invention described in claim 6, the temperature of each section is estimated based on the elapsed time after the start of the generator driving engine. With such a configuration, in addition to the above-described functions and effects, it is not necessary to detect the temperature of each unit with a sensor or the like, so that simplification of the configuration and simplification of arithmetic processing can be achieved, thereby promoting cost reduction and the like. Can be.

According to the present invention, as the elapsed time after the start of the generator driving engine is shorter, the rotation speed of the generator driving engine and the control value of the factor controlled on the generator side are reduced. The exhaust gas temperature of the generator driving engine can be further increased. With such a configuration, by utilizing the correlation between the elapsed time after the start of the generator driving engine and the temperature of the exhaust purification catalyst, the catalyst temperature does not have to be detected by a sensor or the like. By simplifying the configuration and arithmetic processing, cost reduction can be promoted, and when the elapsed time after startup is short and the degree of activity of the catalyst is low, the exhaust gas temperature is raised as much as possible to achieve early activation. In addition to the simple and inexpensive configuration, the catalyst temperature can be changed to an efficient operating point by lowering the exhaust gas temperature as the degree of activity of the catalyst progresses with the progress of the elapsed time after the start. Early activation and reduction of fuel consumption can be achieved at the same time.

In the invention described in claim 8, the exhaust temperature of the generator driving engine is increased by increasing the rotation speed of the generator driving engine. With such a configuration, the rotation speed of the generator driving engine is increased,
By lowering the control value of the factor controlled on the generator side, the characteristic that the exhaust temperature of the generator driving engine can be increased even with the same power generation amount, with a simple configuration and high accuracy, It is possible to increase the exhaust gas temperature while maintaining the required power generation amount.

According to the ninth aspect of the present invention, the temperature of each part includes a temperature of a predetermined component disposed in the engine room. With this configuration, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine), for example, basically achieves the required power generation. While power generation (operation) is performed as a possible and efficient operating point, for example, under conditions where the temperature of parts in the engine room is high and there is a possibility that functional deterioration of parts may occur, the amount of power generation (Output) can be controlled to change the operating point to a more appropriate operating point according to the component temperature in the engine room while maintaining the required power generation (required output) as much as possible. While maintaining as much as possible, it is possible to suppress the functional deterioration and the like of the components in the engine room.

According to the tenth aspect of the present invention, when the temperature of a predetermined component disposed in the engine room exceeds a set temperature, the rotational speed of the generator driving engine and the rotational speed of the generator are controlled. The control value of the controlled factor is changed so that the required power generation amount can be achieved and the exhaust temperature of the generator driving engine can be reduced. With such a configuration, the operating point of the generator and the engine for driving the generator, for example, can basically achieve the required power generation amount,
In addition, while power generation (operation) is performed as an efficient operating point, under conditions where the temperature of parts in the engine room is high and there is a risk of functional deterioration of the parts, etc. Based on the correlation with the temperature, the exhaust gas temperature was reduced while maintaining the required power generation (required output) as much as possible.
It is possible to maintain the temperature of parts in the engine room at an appropriate temperature. Therefore, it is possible to suppress the functional deterioration of components in the engine room and the like while maintaining the required power generation amount as much as possible.

According to the eleventh aspect of the present invention, the temperature of a predetermined component disposed in the engine room exceeds a set temperature, and is controlled by the rotation speed of the generator driving engine and the generator side. Even after the control value of the factor has been changed to a point at which the required power generation amount can be achieved, and the exhaust temperature of the generator driving engine can be lowered, the predetermined parts disposed in the engine room are If the temperature does not fall below the set temperature, the rotation speed of the generator driving engine and the factors controlled on the generator side until the temperature of the predetermined components disposed in the engine room becomes below the set temperature. Is changed in such a direction that the power generation amount is reduced while passing through a point where the exhaust gas temperature of the generator driving engine can be reduced to the maximum at the same power generation amount.

With this configuration, when the temperature of predetermined components disposed in the engine room exceeds a set temperature, first, the temperature in the engine room is reduced in a decreasing direction while maintaining the required power generation amount. In addition to changing the operating point, if the exhaust temperature is not sufficiently lowered even if the operation is performed at this operating point and the temperature of the components in the engine room does not become lower than the set temperature, for example, the operation in which the lowest exhaust temperature is reached with the same power generation amount Point (cooling operation point), the power generation amount is reduced, so that the exhaust temperature of the generator driving engine and the engine temperature are maintained while maintaining the maximum required power generation amount (and hence power performance). The temperature of parts in the room can be reduced most effectively.

[0022]

According to the first and second aspects of the present invention, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine) ), For example, can basically achieve the required power generation,
In addition, while the power generation is performed as an efficient operating point, the power generation amount may be reduced depending on the temperature conditions of each part such as a low catalyst temperature (not in an active state) or a high component temperature in the engine room. Since it is possible to perform control to change the operating point to a more appropriate operating point according to the temperature condition of each part while maintaining the required power generation as much as possible, the temperature condition of each part can be controlled while maintaining the required power generation as much as possible. It is possible to satisfy as much as possible. Therefore, maintaining the required power generation as much as possible,
The exhaust performance can be improved by, for example, early activation of the catalyst, or the protection and deterioration of each component can be suppressed while securing the vibration performance and suppressing the deterioration of the battery.

According to the third aspect of the present invention, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine) are set to the respective parts. While the temperature condition satisfies the predetermined condition, the required power generation can be achieved, and as an efficient operating point,
Since power generation can be performed, for example, it is possible to minimize the fuel consumption of the generator driving engine while maintaining the required power generation amount, securing power performance and the like, and suppressing battery deterioration and the like.

According to the invention described in claim 4, for example,
When the catalyst temperature is low (the catalyst is not active), the operating point of the generator and the generator driving engine (control values of the control factors on the generator side and the rotation speed of the generator driving engine)
Can be generated as an operating point that can achieve the required power generation and raise the exhaust gas temperature, so that the required power generation can be maintained as much as possible to ensure power performance and suppress battery deterioration, etc. In addition, early activation of the catalyst can be achieved as much as possible, so that exhaust performance can be improved.

According to the fifth aspect of the present invention, when the deviation between the temperature of the exhaust gas purification catalyst provided in the exhaust passage of the generator driving engine and the set temperature is large, the exhaust gas temperature is as low as possible. To be activated early by increasing
If the deviation becomes small, the exhaust gas temperature can be lowered and the operating point can be changed to an efficient operating point, so that it is possible to achieve both early activation of the catalyst and reduction of fuel consumption. Becomes

According to the sixth aspect of the present invention, in addition to the above-mentioned effects, the temperature of each part does not have to be detected by a sensor or the like, so that the configuration can be simplified and the arithmetic processing can be simplified. Can promote cost reduction and the like. According to the invention described in claim 7, the catalyst temperature is detected by a sensor or the like by utilizing the correlation between the elapsed time after the start of the generator driving engine and the temperature of the exhaust purification catalyst. Since it is not necessary, the structure can be simplified and the arithmetic processing can be simplified, which can promote cost reduction, etc., and when the elapsed time after startup is short and the degree of activity of the catalyst is low, the exhaust gas temperature should be raised as much as possible. A simple and inexpensive configuration because the exhaust gas temperature can be lowered and the operating point can be changed to an efficient operating point as the degree of activation of the catalyst progresses with the progress of the elapsed time after start-up. However, it is possible to achieve both early activation of the catalyst and reduction of fuel consumption.

According to the eighth aspect of the present invention, the rotational speed of the generator driving engine is increased and the control value of the factor controlled on the generator side is reduced, so that the generator driving engine can be driven at the same power generation amount. By utilizing the characteristic that the exhaust temperature of the engine can be increased, the exhaust temperature can be increased with a simple configuration and with high accuracy while maintaining the required power generation amount. According to the ninth aspect of the present invention, the operating point of the generator and the generator driving engine (the control value of the control factor on the generator side and the rotation speed of the generator driving engine) are basically set, for example, While it is possible to achieve the required power generation amount and to generate power as an efficient operating point, for example, under conditions where the temperature of parts in the engine room is high and functional deterioration of parts may occur, It is possible to perform control to change the operating point to a more appropriate operating point according to the temperature of the components in the engine room while maintaining the required power generation as much as possible. ,
It is possible to suppress functional deterioration of components in the engine room, and the like.

According to the tenth aspect of the present invention, the operating point of the generator and the generator driving engine is, for example, basically the required power generation amount can be achieved and the efficient operating point is used as the operating point. On the other hand, under conditions where the temperature of the components in the engine room is high and there is a risk of causing functional deterioration of the components, the amount of power generation can be made based on the correlation between the exhaust temperature and the temperature in the engine room. Since the exhaust gas temperature is reduced while maintaining the required power generation amount as much as possible, it is possible to maintain the temperature of the components in the engine room at an appropriate temperature. Therefore, while maintaining the required power generation as much as possible,
It is possible to suppress functional deterioration and the like of components in the engine room.

According to the eleventh aspect of the present invention, when the temperature of the predetermined components disposed in the engine room exceeds the set temperature, first, while maintaining the required power generation, the engine room temperature is maintained. Change the operating point in the downward direction,
If the exhaust temperature is not sufficiently lowered even when operating at this operating point and the temperature of the components in the engine room does not become lower than the set temperature, for example, the operating point (cooling operating point) at which the lowest exhaust temperature is reached at the same power generation amount is set. Since the amount of power generation is reduced while passing through, the exhaust gas temperature of the engine for driving the generator and the temperature of parts in the engine room are most effective while maintaining the maximum required power generation (and power performance). Can be reduced.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 2 shows a series hybrid electric vehicle (S) according to the first embodiment of the present invention.
1 shows the system configuration of HEV). As shown in FIG. 2, the SHEV according to the first embodiment includes a generator driving engine 10, a generator 11 used for power supply, a battery 12 for storing and supplying energy, and energy regeneration during driving and deceleration of the vehicle. Driving motor 13 used in the vehicle, a transmission system 14 for transmitting the output of the vehicle driving motor 13 to driving wheels 15, a reduction gear and the like, and a control device 16 for controlling these
Consists of

The vehicle drive motor 13 receives power supply from one or both of the battery 12 and the generator 11. Normally, when the energy corresponding to the required output of the vehicle drive motor 13 is in the battery 12, that is, when the battery 12 is in a sufficiently charged state, the vehicle drive motor 13 is driven by the energy of the battery 12 to generate power. The engine 10 and the generator 11 are not driven.

When the energy of the battery 12 does not satisfy the required output of the vehicle drive motor 13 or falls below a predetermined charge amount, the generator drive engine 10 is driven, and the Generator 1 directly connected via a transmission or a transmission or a belt
1 is used for supplying drive energy to the vehicle drive motor 13 and charging the battery 12.

When the charged amount of the battery 12 satisfies the required output of the vehicle drive motor 13 again, or when the battery 12 reaches a predetermined charged amount, the generator driving engine 10 is turned off. Stop the generator 1
1 to stop the power generation. The control device 16 controls input / output of the vehicle drive motor 13, charging / discharging of the battery 12, output of the generator 11, and starting / starting of the generator drive engine 10.
Stop, ON / OFF of battery input / output relay 17,
It controls a throttle valve and the like that is attached to the generator driving engine 10 and controls the amount of intake air.

A water temperature sensor 18 is attached to the generator driving engine 10, and this signal is transmitted to a control device 16.
Is to be read. A catalyst 19 serving as an exhaust gas purification system is installed in an exhaust pipe downstream of the engine 10, and a temperature sensor 20 is attached to the catalyst 19, and a detection signal of the temperature sensor 20 is read into the control device 16. It has become.

FIG. 3A shows the engine speed (the engine speed or the engine speed; the same applies hereinafter) and the engine load 駆 動, ie, the driving reaction force (generator driving torque) of the generator 11. It changes according to the output current value, terminal voltage, and the like. FIG. 3B shows an equal output line and an equal intake air flow line on the operation map｝, and FIG. 3B is replaced with a relationship between the engine speed and the intake air flow when the same output is maintained. is there. As shown here, when the same output (and hence the same amount of power generation) is maintained, the intake air flow rate does not substantially change even when the engine speed is changed, and the same output (and hence the same amount of power generation) will be maintained. If
It can be seen that the intake air flow rate is constant.

FIG. 4A shows an equal output line and an equal engine exhaust temperature line on the operation MAP of the engine rotation and the engine load (the driving reaction force of the generator 11).
(B) replaces the relationship between the engine speed and the exhaust temperature when the same output (and hence the same amount of power generation) is maintained. As shown here, when the engine output is maintained at the same output (and thus the same power generation amount), the exhaust temperature tends to increase when the engine speed is increased, but the engine speed decreases when the engine speed is lower than a certain engine speed. It can be seen that there is a region where the exhaust gas temperature rises in reverse.

FIG. 5 (A) shows an equal output line and an equal engine fuel efficiency line on the operation MAP of the engine rotation and the engine load (the driving reaction force of the generator 11).
(B) replaces the relationship between the engine speed and the fuel efficiency when the same output (and hence the same amount of power generation) is maintained. As can be seen from FIG. 5A, generally, the good fuel economy of the engine is due to the fact that the engine speed is 2000 to 2000
It is set on the high load side of 4000 rpm.

When arranged as shown in FIG. 5B, the engine speed is increased while maintaining the same output (and hence the same amount of power generation). It will be understood that when the engine load is reduced, the fuel efficiency tends to deteriorate. It can also be seen that there is a region where the fuel efficiency tends to deteriorate when the rotational speed is equal to or less than a certain rotational speed (more than a certain load).

FIG. 6 shows the basic operating points of the generator 11 and the generator driving engine 10. Basically, when there is no condition restriction due to exhaust gas, heat, etc., the operation of the generator 11 and the generator driving engine 10 is performed at a point of high efficiency (fuel efficiency) (APU basic operating point). ing. Therefore, when the operating points for each output (APU basic operating point) are linked, an operating line as shown by a thick solid line in FIG. 5 can be drawn on the MAP, and the operating line on the MAP can be drawn according to the required power generation output value (the required power generation amount). In view of the above, the engine speed of the generator driving engine 10 and the engine load ｛, that is, the generator 11
And the command value (control value) of the current reaction and the terminal voltage according to the output (power generation amount).

FIG. 7 shows the operating points of the generator 11 and the generator driving engine 10 when the catalyst 19 has a low exhaust gas purification capacity and a low temperature (inactive). If the required power generation output is determined, the APU basic operating point on the basic operating line shown in FIG. 6 can be uniquely determined, but when the temperature of the catalyst 19 is low (low activity), the exhaust gas Since the exhaust gas is not purified and the exhaust gas concentration is high, a large amount of exhaust harmful components are emitted. Therefore, there is a demand to raise the temperature of the catalyst 19 as soon as possible.

As a method of raising the temperature of the catalyst 19 at an early stage, the power generation output (engine output) as described above is used.
There is a way to increase the power generation output (engine output)
Is to be originally calculated (determined) from information such as the state of charge of the battery. Therefore, regardless of the information such as the state of charge of the battery, it is impossible to change the power generation output (engine output) indiscriminately. It should be avoided because it may cause deterioration and adverse effects on other units.

Therefore, in the present embodiment, attention is paid to the exhaust gas temperature characteristic of the generator driving engine 10 as shown in FIG. 4, that is, the engine speed is increased and the engine load (driving torque extension of the generator 11) is increased. Output current value, terminal voltage, etc.)
By using the characteristic that the exhaust gas temperature can be increased while maintaining the same output (same power generation amount) by lowering the catalyst temperature, the temperature of the catalyst 19 becomes higher than the set temperature (activation temperature) at which the catalyst 19 exhibits good purification performance. In the case below, as shown in FIG. 7, according to the deviation (or ratio or the like) between the set temperature and the current catalyst temperature, the basic operating point X is set to a value such as X ′ on the equal output line. The shift is made to the operating point (the shift is made to increase the engine rotation speed as the deviation increases).

Thus, the required power generation output (required power generation)
, The catalyst 19 can be raised to the exhaust gas purification temperature (activation temperature) at an early stage, so that the exhaust gas purification performance can be improved at an early stage. Then, when the same power generation request output continues and the operation is continued at X ′, the temperature of the catalyst 19 gradually increases, and the deviation from the set temperature is reduced. Transition,
Further, when the temperature of the catalyst 19 rises (the deviation decreases),
In accordance with this, the operating point is shifted from X "to an operating point approaching X, and in the present embodiment, the operating point is set to the basic operating point X when the temperature of the catalyst 19 becomes equal to or higher than the set temperature. Control is performed.

By the way, a series hybrid electric vehicle (SHEV) includes a vehicle drive motor 13 and a generator 1.
1, a generator driving engine 10, a control device 16 for controlling them, various sensors, etc. are provided. However, due to layout problems, these units are arranged in the same space as the generator driving engine 10, for example, a gasoline engine vehicle. In some cases, it may be disposed in an engine room, and may be exposed to a high ambient temperature.

Since the microcomputer and various sensors used in the control device 16 do not have a very high function guarantee temperature, the temperature of these components must be controlled to be equal to or lower than the function guarantee temperature. As shown in FIG. 9, the ambient temperature in the engine room has a deep relationship with the engine exhaust temperature, and the two are approximately proportional. Therefore, if the engine exhaust temperature is lowered, the temperature in the engine room can be lowered, and thus the temperature of the microcomputer and various sensors used in the control device 16 can be lowered.

In the engine operating range, the engine speed at the lowest exhaust temperature point at the same output shown in FIG. 4 does not always match the engine speed at the highest fuel efficiency point at the same output shown in FIG. do not do. FIG. 8 shows a case where the engine speed at the highest efficiency point (highest fuel efficiency point), which is the basic operating point, is lower than the engine speed at the lowest exhaust temperature point at the same output.

Therefore, in the case of the characteristic shown in FIG.
In the present embodiment, the following control is performed to effectively reduce the exhaust gas temperature. That is, when a certain power generation request output is determined, the operating points of the generator 11 and the generator driving engine 10 are determined to be Y on the basic operating point. However, the temperature in the engine room rises,
When the temperature of the microcomputer / sensor or the like exceeds a predetermined temperature, it is necessary to lower the temperature in the engine room in order to lower these temperatures.

In such a case, it is conceivable to lower the engine room temperature by moving the operating point along the basic operating line (highest fuel efficiency point) to lower the engine output (power generation output). However, such a method does not necessarily
Since the exhaust gas temperature cannot be lowered effectively, there is a high possibility that the required output of power generation will not be sufficiently reached without sufficiently lowering the exhaust gas temperature. There is fear.

In other words, if the engine speed at the lowest exhaust temperature point matches the engine speed at the highest fuel efficiency point at the same output, the basic operation line (highest fuel efficiency point)
If the operating point is moved along the range, the exhaust gas temperature can be reduced most effectively because it passes through the lowest exhaust gas temperature point at the same time. Therefore, there is a case where it is not possible to obtain a reduction in the exhaust gas temperature even if the power generation output (engine output) is reduced.

Therefore, in the present embodiment, in the case of the characteristic as shown in FIG. 8, the operation at the same output point where the engine load (generator load) is reduced by slightly increasing the engine speed from the basic operating point Y is performed. Utilizing the characteristic that the point Y ′ is an operating point capable of lowering the exhaust gas temperature while having the same output as the basic operating point Y, when the temperature is restricted, first,
Control is performed to shift the basic operating point Y to the operating point Y '.

As a result, it is possible to control the temperature in the engine room in a decreasing direction while outputting the required power generation amount. If the decrease in exhaust gas temperature is not sufficient even at the operation point Y ', the engine output is reduced on the cooling operation point connecting the operation points having the same output and the lowest exhaust gas temperature (Y "). Shift to).

As a result, the exhaust gas temperature of the engine can be reduced most effectively while maintaining the maximum required power generation amount. FIG. 10 is a control flowchart incorporating the above-described concept of the present invention. Here, in accordance with the flowchart of FIG.
The operation control of 0 will be described in more detail.

Starting from START, first, in S101, the charged capacity SOC (remaining capacity) of the battery 12 and the charged capacity change amount 容量 SOC of the battery 12 are read. S1
In 02, it is determined from these information whether power generation is necessary. If there is no need, the process returns (ie, returns to the main control routine not shown). If it is determined that power generation is necessary, the process proceeds to S103.

At S103, the generator driving engine 10
To start. Then, in S104, the SOC or the △ SO
C, the required power generation (required power generation) P0
Decide. The method of determining the power generation amount may be the same as the conventional method. In S105, referring to the basic operation MAP (for example, the map in FIG. 5) set in the control device 16 in advance,
Engine speed command value N0 that can achieve power generation request amount P0
And a generator load (engine load) T0 (basic operating point). The generator load (engine load) corresponds to the driving reaction force of the generator 11, that is, a command value (a power generation amount control factor of the generator 11 necessary for obtaining the required power generation amount at the engine speed N0). Control value) (output current value, terminal voltage, etc.).

In step S106, the current temperature tc of the catalyst 19 is calculated.
It is determined whether at is higher or lower than the set temperature tc at which the catalyst 19 exhibits the purification performance. If it is higher, the process proceeds to S109. If the temperature has not reached the set temperature (low), S107
Then, in S107, the set temperature tc and the catalyst temperature tc
At temperature difference Δt is calculated. In the following S108, △
The engine speed command value N0 and the generator load command value T0 are corrected to an operating point determined in advance for each output according to t, that is,
The engine speed command value is replaced with Ncol, and the generator load command value is replaced with Tcol, and the process proceeds to S109. That is, for example, the operating point X in FIG. 6 is changed to X ′ according to Δt,
Control is performed such that the operating point is changed to X "in accordance with the subsequent reduction in Δt, and the operating point is gradually returned to the operating point X in accordance with the further reduction in Δt.

In step S109, the temperatures ta, tb, tc,... Of the microcomputer and various sensors are set to the set temperatures tah, tbh, tch,.
-It is determined whether or not it has reached. If not reached, the process proceeds to S114 and S115, and the engine speed command value and the generator load command value determined in S105 or S108 are set as operation command values, and the process returns.

On the other hand, if it is determined in step S109 that the temperatures of the respective parts exceed the set temperatures, the process proceeds to step S110. In S110, it is determined whether or not the current operating point is operating at the lowest exhaust temperature point during the same output, that is, the cooling operating point. If it is not the cooling operation point, the engine speed Nhea is the cooling operation point stored in advance in the control device 16 for each output.
t, The operating point command value is changed to the generator load Theat. That is, for example, control is performed to change the operating point Y in FIG. 8 to Y ′.

On the other hand, if it is determined in S110 that the operation has already been performed at the cooling operation point, the required power generation amount P0
Is changed to the power generation amount P1 in which the output is reduced by ΔP, and the engine speed N1heat and the generator load T1heat are determined at the cooling operation point. That is, for example, the operating point Y ′ in FIG. 8 is first changed to Y ″, and if the temperature of each section still exceeds the set temperature, the output is reduced along Y ′ along the operating line connecting the cooling operating points. The control which goes is performed.

The value determined in S111 or S113 is output as an operation command value in S114 and S115, and the routine returns. As described above, according to the first embodiment, the operating point of the generator and the generator driving engine is basically operated at the efficient operating point in accordance with the required output (required power generation amount). On the other hand, under conditions such as when the catalyst temperature is low (not in an active state) or when the temperature of parts in the engine room is high, the output (power generation amount) is maintained at the required output (required power generation amount) as much as possible. Since the control for changing the operating point to an appropriate value can be performed, the temperature condition of each part can be satisfied as much as possible while maintaining the required power generation amount as much as possible. Therefore, while maintaining the required power generation as much as possible, ensuring power performance, noise / vibration performance, and suppressing battery deterioration, it is possible to improve exhaust performance by, for example, early activation of the catalyst, or to protect each component. And deterioration and the like can be suppressed.

In this embodiment, the operating point is changed according to the temperature of the catalyst 19 and the operating point is changed according to the temperature of each part such as the microcomputer and various sensors. However, the present invention is not limited to this. , The operating point can be changed only in accordance with one of the temperature of the catalyst 19 and the temperature of each part such as a microcomputer and various sensors. That is, S106 to S106 in the flowchart of FIG.
It is also possible to adopt a configuration in which one of the processing in S108 and the processing in S109 to S113 is omitted.

Next, a second embodiment of the present invention will be described. FIG. 11 illustrates a control method according to the second embodiment. In the second embodiment, in view of the catalyst temperature has a certain correlation with the elapsed time from the start of the engine, the starting temperature is set so that the required output can be achieved and the exhaust temperature can be increased after the start, This operating point is controlled so as to approach the basic operating point in accordance with the elapsed time after starting (in other words, the degree of increase in the catalyst temperature).

As shown in FIG. 11, when the operating points set according to the elapsed time after the start are connected for each output, the operation line for each elapsed time after the start (t0, t1, t2...) Is obtained. Can be drawn. Then, in the present embodiment, for example, at the time t1 after the start, the control is performed to the operating point (for example, Z2) at which the required output is obtained on the line of t1.

In this manner, the exhaust gas temperature can be controlled in accordance with the elapsed time after the start so that the purification performance of the catalyst 19 can be exhibited (activated) at an early stage while achieving the required power generation amount. Becomes FIG. 12 shows a generator 11 and an engine 10 according to the second embodiment.
5 is a flowchart for explaining the operation control of FIG.

Hereinafter, the flowchart of FIG. 12 will be described. Note that S201 to S204 and S109 and subsequent steps are the same as S101 to S104 and S109 and subsequent steps in the flowchart of FIG. 10 according to the first embodiment, and a description thereof will be omitted. In S205, since the engine has been started, the operating point MAP for each output preset in the control device 16 is referred to at the elapsed time t0 after the start, and the engine speed Nt0 and the required output (required power generation amount) P0 are referred to. The generator load Tt0 is determined.

In S206, the elapsed time t after the engine is started is t
Start is read, and it is determined by S207, S208, S210 and the like how much time has elapsed since the start. Then, in S209, S211, and S212, the engine speed and the generator load set in advance according to the required output (required power generation amount) are determined as command values with reference to FIG. That is, as shown in FIG. 11, from the operating point Z1 at which the exhaust gas temperature can be maximized while satisfying the required output, the operating point is gradually changed to the operating point Z2 as the elapsed time after starting increases. , Z
Control to shift to 3, Z is performed.
In other words, from the operating point at which the exhaust gas temperature on the iso-output line is maximized, the operating point at which the exhaust gas temperature decreases as the elapsed time after startup increases (as the catalyst 19 approaches the activated state). Moving to (Z2, Z3), the operation point is shifted to the operating point (Z) where the maximum fuel efficiency is obtained.

Then, S207, S209, S21
After S1, S212, the same processing as in the first embodiment (S
109 to S115) are performed. As described above, according to the second embodiment, the operating point of the generator and the generator driving engine is basically operated at an efficient operating point in accordance with the required output (required power generation amount). On the other hand, under conditions such as a low catalyst temperature (not in an active state) (e.g., a configuration predicted from the elapsed time after starting) or a condition such as a high component temperature in an engine room, an output (power generation amount) can be obtained. The control to change the operating point to an appropriate value while maintaining the required output (required power generation) as much as possible can be performed, so that the required power generation can be maintained as much as possible and the temperature conditions of each part can be satisfied as much as possible. it can. Therefore,
While maintaining the required power generation as much as possible and ensuring power performance, noise and vibration performance, and suppressing battery deterioration, for example,
Exhaust performance can be improved by early activation of the catalyst, or protection and deterioration of each component can be suppressed.

In the first embodiment, a temperature sensor 20 for detecting the temperature of the catalyst 19 is provided, and the operation method after the start is most effectively determined by monitoring the catalyst temperature. On the other hand, in the second embodiment, since the effective operation method after the start is determined based on the elapsed time after the start, the temperature sensor 20 can be eliminated, and the cost can be reduced. Also, the arithmetic processing can be simplified.

In the present embodiment, the operating point is changed according to the elapsed time after the start-up, {operating point} according to the temperature of the catalyst 19 (active state), and operating point according to the temperature of each part such as a microcomputer and various sensors. However, the present invention is not limited to this, and the operating point can be changed only in accordance with the elapsed time after the start. That is,
S after S206 to S212 in the flowchart of FIG.
A configuration in which the processes of 109 to S113 are omitted may be adopted.

In each of the above embodiments, the temperature conditions of each part include the temperature condition of the exhaust purification catalyst (the temperature condition can be referred to as the temperature condition of the generator driving engine) and the components in the engine room. Although the temperature conditions of the microcomputer (various sensors, etc.) have been representatively described, the present invention is not limited to this. For example, the present invention can change the engine warm-up characteristics according to the engine water temperature while maintaining the power generation amount as much as possible. The method can be applied to the case where the operating point is changed as described above, or the case where the operating point is changed to limit the engine water temperature or the drive motor temperature to a predetermined temperature or less while maintaining the power generation amount as much as possible. It is.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of the present invention.

FIG. 2 is a system configuration diagram according to the first embodiment of the present invention.

FIG. 3A is a diagram showing an equal output line and an equal intake air flow line with the horizontal axis representing the engine speed and the vertical axis representing the engine load. (B) is a diagram showing a relationship between the engine rotation speed and the intake air flow rate for each output based on (A).

FIG. 4A is a diagram showing an equal output line and an equal exhaust temperature line with the horizontal axis representing the engine rotation speed and the vertical axis representing the engine load. (B) is a diagram showing a relationship between the engine speed and the exhaust temperature for each output based on (A).

FIG. 5A is a diagram showing an equal output line and an equal fuel consumption line with the horizontal axis representing the engine speed and the vertical axis representing the engine load. (B) is a diagram showing a relationship between the engine speed and the fuel efficiency for each output based on (A).

FIG. 6 is a diagram showing a curve connecting operating points (APU basic operating points) at which the best fuel efficiency is obtained for each output, with the horizontal axis representing the engine speed and the vertical axis representing the engine load.

FIG. 7: When the catalyst has a low exhaust gas purification ability at low temperatures (inactive)
FIG. 7 is a diagram showing a modified example (X ′ → X ″ → X) of the operating points of the generator 11 and the generator driving engine 10 in FIG.

FIG. 8 shows an example of changing the operating points of the generator 11 and the generator driving engine 10 for effectively lowering the exhaust gas temperature (Y →
Y ′ → Y ″).

FIG. 9 is a diagram showing a correlation between an engine exhaust temperature and an engine room temperature.

FIG. 10 is a control flowchart according to the first embodiment of the present invention.

FIG. 11 is a diagram for explaining an operating point set for each output in accordance with the elapsed time after starting.

FIG. 12 is a control flowchart according to the second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Engine for driving a generator 11 Generator 12 Battery 13 Electric motor for driving a vehicle 16 Controller 18 Water temperature sensor 19 Catalyst 20 Catalyst temperature sensor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Hirano 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Nissan Motor Co., Ltd. (72) Inventor Tsuyoshi Aso 2 Takaracho, Kanagawa-ku, Yokohama City, Kanagawa Nissan Motor Co., Ltd. 72) Inventor Ryuichi Wellguchi, Nissan Motor Co., Ltd., 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture (72) Inventor Yutaro Kaneko, 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture, Nissan Motor Co., Ltd.

Claims (11)

[Claims] 1. An electric motor for driving a vehicle, a chargeable / dischargeable storage battery for supplying electric power to the electric motor for driving a vehicle, and an electric power generation for supplying electric power to the electric motor for driving the vehicle or the storage battery. A generator, and a generator driving engine for driving the generator, wherein a rotation speed is controlled by the generator driving engine among the factors for controlling the power generation amount of the generator. In the power generation control device for an electric vehicle, wherein factors other than the above are controlled on the generator side, control of the rotation speed of the generator driving engine and the factors controlled on the generator side in accordance with the temperature conditions of each part. A power generation control device for an electric vehicle, wherein the value is changed. 2. An electric motor for driving a vehicle, a chargeable / dischargeable storage battery for supplying power to the electric motor for driving a vehicle, and a power generator for supplying electric power to the electric motor for driving the vehicle or the storage battery. A generator, and a generator driving engine for driving the generator, wherein a rotation speed is controlled by the generator driving engine among the factors for controlling the power generation amount of the generator. In the power generation control device for an electric vehicle, wherein factors other than the above are controlled on the generator side, control of the rotation speed of the generator driving engine and the factors controlled on the generator side in accordance with the temperature conditions of each part. A power generation control device for an electric vehicle, comprising change control means for changing a value. 3. When a temperature condition of each section satisfies a predetermined condition, a control value of a rotation speed of the generator driving engine and a control value of a factor controlled on the generator side achieve a required power generation amount. 3. The power generation control device for an electric vehicle according to claim 1, wherein the power generation control device is configured to be configured to be able to increase the efficiency of the generator driving engine. 4. 4. When the temperature of an exhaust purification catalyst interposed in an exhaust passage of the generator driving engine is equal to or lower than a set temperature,
The control value of the rotation speed of the generator driving engine and a factor controlled on the generator side can achieve the required power generation amount,
The power generation control device for an electric vehicle according to any one of claims 1 to 3, wherein the power generation control device is configured to be able to increase the exhaust temperature of the generator driving engine. . 5. The rotational speed of the generator driving engine and the generator as the deviation between the temperature of the exhaust purification catalyst interposed in the exhaust passage of the generator driving engine and the set temperature increases. The control value of a factor controlled on the side is changed to a point at which the exhaust temperature of the generator driving engine can be further increased.
A power generation control device for an electric vehicle according to Claim 1. 6. The electric vehicle according to claim 1, wherein the temperature of each section is estimated based on an elapsed time after a start of the generator driving engine. Power generation control device. 7. As the elapsed time after the start of the generator driving engine is shorter, the rotation speed of the generator driving engine and the control value of a factor controlled on the generator side are increased. 7. The power generation control device for an electric vehicle according to claim 6, wherein the temperature of the exhaust gas can be further increased. 8. The generator according to claim 4, wherein an exhaust gas temperature of the generator driving engine is increased by increasing a rotation speed of the generator driving engine. Power generation control device for electric vehicles. 9. The electric vehicle according to claim 1, wherein the temperature of each part includes a temperature of a predetermined component disposed in an engine room. Control device. 10. A control value of a rotation speed of the generator driving engine and a factor controlled on the generator side when a temperature of a predetermined component disposed in the engine room exceeds a set temperature. The power generation control device for an electric vehicle according to claim 9, wherein the power generation control device is configured to be able to achieve a required power generation amount and to reduce an exhaust temperature of the generator driving engine. . 11. The temperature of a predetermined component disposed in the engine room exceeds a set temperature, and a control value of a rotation speed of the generator driving engine and a control value of a factor controlled on the generator side are required. Even if it is possible to achieve the power generation amount, and even after being changed to the point that the exhaust temperature of the generator driving engine can be lowered, if the predetermined parts disposed in the engine room do not become lower than the set temperature. Until the temperature of predetermined components disposed in the engine room becomes equal to or lower than a set temperature, the rotation speed of the generator driving engine and the control value of the factor controlled on the generator side are the same power generation. 10. The electric power generation system according to claim 9, wherein the power generation amount is changed in a direction in which the power generation amount is reduced while passing through a point at which the exhaust temperature of the generator driving engine can be reduced as much as possible. Control device.